Rotation detection device and manufacturing method for the same

ABSTRACT

A rotation detector component detects a rotational state of a rotor and sends a rotational detection signal. A signal transmission component is electrically connected with a lead frame of the rotation detector component to transmit the rotational detection signal to an external device. A body portion holds the rotation detector component and a part of the signal transmission component. The body portion is integrally molded of a first resin to cover a joint portion between the lead frame and the signal transmission component, the rotation detector component, and a part of the signal transmission component. A part of the rotation detector component forms an exposed portion exposed from the body portion.

CROSS REFERENCE TO RELATED APPLICATION

This application is based on reference Japanese Patent Application No.2011-264858 filed on Dec. 2, 2011, the disclosure of which isincorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a rotation detection device includinga rotation detector component, a signal transmission component, and abody portion. The present disclosure further relates to a manufacturingmethod for the rotation detection device.

BACKGROUND

For example, JP-A-2005-227095 discloses one example of a magnetismsensor including a magnetoelectric conversion element, which ispositioned with high accuracy when molded of a resin material. Themagnetism sensor of JPA-2005-227095 includes a plate-like lead terminal,which is molded of a resin material entirely, while being held by aholder of the magnetoelectric conversion element at two or more placesand positioned at two or more places in both the thickness direction ofthe lead terminal and the width direction of the lead terminal.

U.S. Pat. No. 6,157,186, which corresponds to JP-A-H11-014644, disclosesanother example of a rotation detection device having a simplifiedconfiguration with reduced number of components and excellent in waterresistance. The rotation detection device of U.S. Pat. No. 6,157,186includes a casing main body, a magnet, a magnetism detection element,and an encapsulation material. More specifically, the casing main bodyis integrally molded with a connector portion connected to a signalprocessing circuit. The magnet is equipped in a recessed portion of thecasing main body. The encapsulation material is molded of a resinmaterial charged to embed the signal processing circuit therein.

In the configuration of U.S. Pat. No. 6,157,186, the magnetoelectricconversion element held by the holder is entirely sheathed with a resinmaterial. Therefore, the magnetism sensor of U.S. Pat. No. 6,157,186 isformed to include the holder. Consequently, the magnetism sensor of U.S.Pat. No. 6,157,186 cannot be formed to be smaller than the holder.

Furthermore, U.S. Pat. No. 6,157,186 teaches a configuration in which amelting resin material is charged into the recessed portion of thecasing main body, which accommodates the circuit board, the magnet, andthe hall element (magnetism detection element), to encapsulate theaccommodated components. In the present configuration, the rotationdetection device is molded to include the casing main body and theencapsulation material. Therefore, the magnetism sensor of U.S. Pat. No.6,157,186 cannot be formed to be smaller than the casing main body. Inaddition, an additional manufacturing period and a manufacturing burdenare required to accommodate the circuit board, the magnet, and the hallelement in the recessed portion.

SUMMARY

It is an object of the present disclosure to produce a rotationdetection device having a downsized configuration. It is another objectof the present disclosure to produce a manufacturing method for therotation detection device with less manufacturing period and burden.

According to an aspect of the present disclosure, a rotation detectiondevice comprises a rotation detector component configured to detect arotational state of a rotor and to send a rotational detection signal.The rotation detection device further comprises a signal transmissioncomponent electrically connected with a lead frame of the rotationdetector component and configured to transmit the rotational detectionsignal to an external device. The rotation detection device furthercomprises a body portion holding the rotation detector component and apart of the signal transmission component. The body portion isintegrally molded of a first resin, after joining the lead frame of therotation detector component with the signal transmission component toform a joint portion between the lead frame and the signal transmissioncomponent, to cover the joint portion, the rotation detector component,and a part of the signal transmission component. A part of the rotationdetector component forms an exposed portion exposed from the bodyportion.

According to another aspect of the present disclosure, a manufacturingmethod for a rotation detection device, the rotation detection devicecomprising a rotation detector component configured to detect arotational state of a rotor and to send a rotational detection signal.The rotation detection device further comprises a signal transmissioncomponent electrically connected with a lead frame of the rotationdetector component and configured to transmit the rotational detectionsignal to an external device. The rotation detection device furthercomprises a body portion holding the rotation detector component and apart of the signal transmission component. The rotation detection devicefurther comprises a mount portion configured to mount the body portion.The manufacturing method comprises joining the lead frame of therotation detector component with the signal transmission component toform a joint portion between the lead frame and the signal transmissioncomponent. The manufacturing method comprises forming the body portionof the first resin by integrally molding the joint portion, the rotationdetector component, and a part of the signal transmission component,such that a part of the rotation detector component has an exposedportion, which is exposed from the body portion.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the presentinvention will become more apparent from the following detaileddescription made with reference to the accompanying drawings. In thedrawings:

FIG. 1 is a perspective view showing a rotation detection deviceaccording to a first embodiment;

FIGS. 2A and 2B are schematic views each showing a rotation detectorcomponent of the rotation detection device according to the firstembodiment;

FIGS. 3A, 3B, and 3C are schematic views each showing a joint processfor the rotation detection device;

FIG. 4 is a perspective view showing the rotation detection device,which is to be integrally molded;

FIGS. 5A, 5B, 5C, and 5D are views each showing the rotation detectiondevice, which is integrally molded of a first resin;

FIGS. 6A, 6B, 6C, and 6D are views each showing the rotation detectiondevice, in which an exposed portion is sheathed with a second resin;

FIGS. 7A and 7B are views each showing a mount portion of the rotationdetection device according to the first embodiment;

FIG. 8 is a view showing a rotation detection device according to asecond embodiment;

FIG. 9 is a view showing a rotation detection device according to athird embodiment; and

FIGS. 10A and 10B are views each showing a rotation detection device,which is integrally molded of the first resin, according to anotherembodiment.

DETAILED DESCRIPTION Embodiments

As follows, embodiments of the present disclosure will be described withreference to drawings. In the following description, “connect” or“connected” represent an electrically connected configuration. In thefollowing description, explanation about the vertical direction in theupper and lower direction and explanation about the horizontal directionin the left and right direction are supposed to be explaining theconfiguration in the relevant drawing.

First Embodiment

The present first embodiment will be described with reference to FIG. 1to FIG. 7A. FIG. 1 is a perspective view showing a rotation detectiondevice viewed from its lower side. The rotation detection device 10shown in FIG. 1 includes a rotation detector component 11, a bodyportion 12, a signal transmission component 13, and the like. Therotation detection device 10 may further include a mount portion 16(FIG. 7A) optionally. The rotation detector component 11 has a frontsurface close to sensor elements 11 a. The rotation detector component11 has a rear surface opposed to the front surface and distant from thesensor elements 11 a.

Referring to FIG. 1, the rotation detector component 11 includes thebody portion 12 molded of a resin material in a forming machine. Theforming machine may be an injection molding machine, a compactingmachine, or the like. The body portion 12 has an end surface 12 a havingan exposed portion 11 e. The exposed portion 11 e is a part of therotation detector component 11 and is projected from the rotationdetector component 11. The exposed portion 11 e is exposed from the bodyportion 12 to the outside. The exposed portion 11 e is a tip end of therotation detector component 11 and is distant from a joint portion 14(FIG. 5A). In FIG. 1, a holding member 20 includes a first die 21 and asecond die 22 shown by the two-dot chain lines. The holding member 20holds the rotation detector component 11, when the body portion 12 isintegrally molded of a first resin in the forming machine. The exposedportion 11 e is formed, as a trace, with the holding member 20.

The configuration of the holding member 20 will be described later indetail. When the body portion 12 is molded, the first resin is injectedthrough a runner 30. Generally, the holding member 20 and/or the runner30 may be equipped in the forming machine. It is noted that, the holdingmember 20 and/or the runner 30 may be provided separately from theforming machine. The position and quantity of the holding member 20and/or the runner 30 are determined arbitrary according to the shape ofthe body portion 12, the material of the first resin, and/or the like.In the present embodiment, the first resin may be epoxy resin.

The rotation detector component 11 is partially exposed from the endsurface 12 a of the body portion 12. The partially exposed portion ofthe rotation detector component 11 corresponds to the exposed portion 11e. The exposed portion 11 e is the trace of the holding member 20 of theholding rotation detector component 11 when the body portion 12 isintegrally molded. The exposed portion 11 e is held by the holdingmember 20, and therefore, the body portion 12 is not molded on theexposed portion 11 e.

FIGS. 2A and 2B show the rotation detector component 11. Morespecifically, FIG. 2A is a side view showing the rotation detectorcomponent 11, and FIG. 2B is a front view (top view) showing therotation detector component 11. The rotation detector component 11 is asignal processing unit formed by integrally molding a processing circuit11 c with an encapsulation material 11 d. The processing circuit 11 cmay be a semiconductor chip. The encapsulation material 11 d may beselected from various materials, such as a resin material, which canencapsulate (seal) the processing circuit 11 c.

The rotation detector component 11 includes a lead frame 11 b configuredto send a rotational detection signal for detecting a rotational stateof a rotor. In the exemplified configuration of FIG. 2B, the rotationdetector component 11 includes four lead frames 11 b on one side. InFIG. 2A, two of the four lead frames 11 b, which are irrelevant toconnection with the signal transmission component 13, are omitted.Instead of the lead frames 11 b or in addition to the lead frames 11 b,a lead wire, a connecting pin, a terminal, and/or the like may beemployed. The rotor may be a rotational object. The rotor may be, forexample, a hub bearing (FIG. 7A), which will be described later, or maybe a wheel, a rotary electric apparatus, such as a generator, anelectric motor, or a motor alternator, and/or the like.

The rotation detector component 11 shown in FIGS. 2A and 2B isintegrated with the sensor elements 11 a on one side (upper surface,front surface) of the processing circuit 11 c. In FIG. 2A, the upperside may correspond to the front surface, and the lower side maycorrespond to the rear side. The sensor element 11 a is a sensor deviceconfigured to detect the rotational state of the rotor. The sensorelement 11 a may be a magnetic sensor when employed to a rotor equippedwith a magnetism encoder.

As follows, a manufacturing method of the rotation detection device 10will be described with reference to FIG. 3A to FIG. 7B. Themanufacturing method of the rotation detection device 10 includes ajoint process, a body portion molding process, and a mount portionmolding process. As follows, examples of the processes will bedescribed.

[Joint Process]

In the joint process, the lead frame 11 b of the rotation detectorcomponent 11 is joined with the signal transmission component 13. Thesignal transmission component 13 is configured to transmit therotational detection signal, which is sent from the rotation detectorcomponent 11 through the lead frame 11 b, to an external device. Theexternal device is configured to process the rotational detection signaland may be a computer device such as an electronic control unit (ECU).In the present embodiment, the signal transmission component 13 is anelectric wire. More specifically, as shown in FIG. 3A, the signaltransmission component 13 is formed by sheathing a tip end 13 a of anelectric conduction object with an insulation sheathe material 13 b. Theshape of the tip end 13 a may be arbitrary determined. In the presentembodiment, the tip end 13 a is formed by twisting multiple thin wires(thin cores) and welding the twisted thin wires to be in a plate shapeto facilitate joining with the lead frame 11 b. More specifically, thetwisted thin wires are resistance-welded or ultrasonic welded.Furthermore, multiple insulation sheathe materials 13 b are bundled andentirely sheathed with an insulation sheathe material 13 c. In thepresent embodiment, two insulation sheathe materials 13 b are bundledand sheathed. A shielded wire may be interposed between the insulationsheathe material 13 b and the insulation sheathe material 13 c to reduceinfluence of noise and/or the like on the rotational detection signal.

As shown in FIG. 3A, the lead frame 11 b is put onto the tip end 13 a,and the joint process with the signal transmission component 13 isimplemented in the state where the lead frame 11 b is in contact withthe tip end 13 a. The joint is implemented by welding, soldering, or thelike. The joining is for electrical connection and may be implemented inanother way. For example, an electric conduction wire may be woundaround the lead frame 11 b and the tip end 13 a. Alternatively, the leadframe 11 b and the tip end 13 a may be twisted together. FIG. 3A is aside view showing the joined configuration, and FIG. 3C is a front view(top view) showing the joined configuration. In FIG. 3C, the jointportion 14 is the joined portion between the lead frame 11 b and the tipend 13 a. The rotation detector component 11 is lightweight, andtherefore, the state (configuration) shown in FIGS. 3B and 3C can bemaintained, unless large external force is applied to the lead frame 11b and the tip end 13 a being joined together.

Before implementing the body portion molding process to mold integrallyin the forming machine, the rotation detector component 11 is positionedin accordance with the shape of the body portion 12. As shown in FIG. 4,the positioning is implemented by using the holding member 20. Theholding member 20 is configured with multiple dies. In the example ofFIG. 4, the holding member 20 includes the first die 21 and the seconddie 22. The first die 21 and the second die 22 are in contact with eachother via opposed surfaces to form a recessed portion 20 a. The recessedportion 20 a supports and holds a portion of the rotation detectorcomponent 11 (exposed portion 11 e) when the body portion 12 isintegrally molded.

In the holding member 20, which is configured to form the recessedportion 20 a to hold a part of the rotation detector component 11, thefirst die 21 and the second die 22 may arbitrarily have a configurationof the contact surfaces (boundary planes) via which the first die 21 andthe second die 22 are in contact with each other. In the example of FIG.4, the contact surface of the second die 22 has a recess correspondingto the recessed portion 20 a, and the first die 21 has a flat contactsurface. Alternatively, the first die 21 and the second die 22 mayarbitrarily have other various unillustrated configurations. Forexample, the first die 21 may have a contact surface defining a recesscorresponding to the recessed portion 20 a, and the second die 22 mayhave a flat contact surface. Alternatively, both the first die 21 andthe second die 22 may have contact surfaces defining recessed portions,respectively. In this case, the first die 21 and the second die 22 maybe in contact with each other via the contact surfaces to form therecessed portion 20 a. The first die 21 and the second die 22 may beintegrated into a single die defining the recessed portion 20 a. Threeor more dies may be arbitrarily combined to define the recessed portion20 a. The holding member 20, as a whole or in any way, may define therecessed portion 20 a.

The dimension of the recessed portion 20 a substantially coincides withthe dimension of the exposed portion 11 e of the rotation detectorcomponent 11 to avoid misalignment of the rotation detector component 11during the integrally molding. It is noted that, in reality, clearancemay be formed between the rotation detector component 11 and therecessed portion 20 a of the holding member 20 to protect the rotationdetector component 11 from damage. It is also conceivable that thesurface of the rotation detector component 11 and/or the contactsurfaces of the holding member 20 may not match due to, for example,manufacturing error. As a result, the exposed portion 11 e may becovered with an epoxy resin partially or entirely.

[Body Portion Molding Process]

In the body portion molding process, integral molding is implemented sothat the rotation detector component 11 is partially exposed at theexposed portion 11 e. Specifically, the joint portion 14, which arejoined together in the previous joint process, a part of the signaltransmission component 13, and a part of the rotation detector component11 are molded of an epoxy resin to form the body portion 12. In the bodyportion molding process, as shown in FIG. 4, the integral molding isimplemented in the forming machine in the state where a part of therotation detector component 11 is held by the holding member 20. Theintegral molding by using the forming machine is implemented in ageneral method, and therefore, detailed description and illustration ofthe integral molding are omitted. The integral molding of an epoxy resinproduces high adhesive strength. Therefore, high sealing performance(encapsulation) of the rotation detector component 11 and the signaltransmission component 13 can be secured. FIGS. 5A, 5B, 5C and 5D showexamples of the rotation detector component 11 and the signaltransmission component 13, which are integrally molded and are detachedfrom the runner 30 and the holding member 20.

FIGS. 5A, 5B, 5C and 5D further show examples of the body portion 12integrally molded in the body portion molding process. Specifically,FIG. 5A is a front view showing the rotation detector component 11, thesignal transmission component 13, and the body portion 12, and FIG. 5Bis a side view showing the same. FIGS. 5C and 5D are, similarly to FIG.5A, front views respectively showing other examples of the rotationdetector component 11, the signal transmission component 13, and thebody portion 12, which are integrally molded.

In FIG. 5A, the body portion 12 has a mounted portion 12 b at theposition distant from the rotation detector component 11, which isencapsulated. The mounted portion 12 b is integrally molded with themount portion 16 in the mount portion molding process, which will bedescribed later. As shown in FIG. 7B, the mounted portion 12 b has across section partially in a circular outermost periphery includingmultiple arcs. The mounted portion 12 b may have a cross sectionincluding a linear portion (flat surface) and/or a curved portion(curved surface). Referring to FIGS. 6A, 6B, 6C and 6D, the mountedportion 12 b may have a recessed portion 12 c for producing a detachmentavoidance function. The detachment avoidance function restricts themount portion 16, which is integrally molded in the mount portionmolding process described later, from moving in a predetermineddirection, such as the horizontal direction in FIG. 5A, thereby torestrict the mount portion 16 from being detached.

Referring to FIG. 5B, the body portion 12 excluding the mounted portion12 b is substantially in a rectangular parallelepiped shape smaller thanthe mounted portion 12 b in the diameter and the width. In FIG. 5B, theupper side is the front surface side of the body portion 12, and thelower side is the rear surface side of the body portion 12. As describedabove with reference to FIG. 2A, the sensor element 11 a is located onthe front surface side of the body portion 12. The exposed portion 11 e,which is the trace of the holding member 24, is projected from the endsurface 12 a of the body portion 12.

FIGS. 5C and 5D show examples of the exposed portion 11 e different fromeach other in the dimension. Specifically, the exposed portion 11 e inFIG. 5C and the exposed portion 11 e in FIG. 5D are formed by using theholding member 20 having the recessed portion 20 a different in depth(length) in the left direction in FIG. 4. FIG. 5C shows an example ofthe exposed portion 11 e formed by using the recessed portion 20 ahaving the depth less than that of an example of the exposed portion 11e formed by using the recessed portion 20 a shown in FIG. 5A. FIG. 5Dshows an example of the exposed portion 11 e formed by using therecessed portion 20 a having the depth greater than that of an exampleof the exposed portion 11 e formed by using the recessed portion 20 ashown in FIG. 5A. The shape (size) of the exposed portion 11 e projectedfrom the end surface 12 a of the body portion 12 differs according tothe depth of the recessed portion 20 a. The projected length (depth) ofthe exposed portion 11 e is arbitrarily determined in consideration ofthe material of the body portion 12, the configuration of the rotor, theposition of the rotation detection device 10, and the distance of therotation detection device 10 from the rotor. The projected length(depth) of the exposed portion 11 e may be in a range between 1% and 99%of the total length of the body portion 12.

[Sheathing Process]

In the sheathing process, the exposed portion 11 e is sheathed with asecond resin partially or entirely. After implementing the integrallyforming of the body portion 12 in the body forming process, an electricconduction member may be exposed and/or pay be projected in the exposedportion 11 e of the rotation detector component 11. In the presentembodiment, as shown in FIGS. 2A and 2B, the electric conduction memberis a lead frame (tie bar) 11 b exposed at both the left end and theright end. In a condition where the lead frame 11 b is exposed toexternal environment, such as moisture, particulate, and/or the like, tocause corrosion, short-circuit, and/or the like, the rotation detectorcomponent 11 may cause malfunction.

In consideration of this, the sheathing process is implemented in aconfiguration in which the lead frame 11 b is exposed from the exposedportion 11 e of the rotation detector component 11. Including the leadframe 11 b, which is exposed, the exposed portion 11 e is sheathed withthe second resin to be sealed partially or entirely. In the presentembodiment, the second resin may be an epoxy resin, similarly to thefirst resin. The sheathing an object with an epoxy resin may beimplemented in a general method by using a general forming machine, andtherefore, detailed description and illustration of the method and theforming machine are omitted. FIGS. 6A, 6B, 6C, and 6D show examples ofthe exposed portion 11 e sheathed with an epoxy resin partially orentirely.

FIGS. 6A, 6B, 6C, and 6D respectively show examples of the exposedportion 11 e. In the example shown in FIG. 6A, entire of the exposedportions 11 e and a part of the body portion 12, which is on the side ofthe end surface 12 a, are sheathed with an epoxy resin 15. In theexample shown in FIG. 6B, entire of the exposed portions 11 e issheathed with the epoxy resin 15. In the example shown in FIG. 6C, theend portion of the exposed portions 11 e is sheathed with the epoxyresin 15. The end portion of the exposed portions 11 e includes entireof the tip end surface on the opposite side from the body portion 12. Inthe example shown in FIG. 6D, a part of the tip end surface of theexposed portions 11 e is sheathed with the epoxy resin 15. In all theseexamples, the lead frame 11 b, which is exposed, is sheathed and sealed.The configuration, in which the exposed lead frame 11 b is sheathed andsealed, is not limited to the examples of FIGS. 6A, 6B, 6C, and 6D andmay employ other various configurations.

[Mount Portion Molding Process]

In the mount portion molding process, the mount portion 16 is integrallymolded of a third resin, such that the body portion 12, which is formedin the above-described body portion molding process, is partiallycovered with the third resin, and the signal transmission component 13is partially covered with the third resin. In the present embodiment,the third resin may be a poly butylene terephthalate (PBT). The integralmolding is implemented by using the forming machine in a state where thebody portion 12 is held by a holder (not shown), which is different fromthe holding member 20. In the integral molding, the outermost peripheryof the body portion 12 is melted and is integrally molded with the mountportion 16. The material of the mount portion 16 may be a PBT and may bean epoxy resin similarly to the body portion 12. In a case where theintegral molding (integral forming) is implemented by using a processingmachine other than the above-described forming machine (moldingmachine), the material of the mount portion 16 may be another material,such as a metallic material, a carbon fiber, or the like, than a resinmaterial.

FIGS. 7A and 7B show the rotation detector component 11, which isintegrally molded. FIG. 7A is a side view showing the rotation detectorcomponent 11, and FIG. 7B is a sectional view taken along the line(arrow) VIIB-VIIB in FIG. 7A. In FIG. 7A, the two-dot chain linerepresents a rotor 40 being the detection object of the sensor element11 a (FIG. 2A), which is equipped to the rotation detector component 11for detecting the rotational state. In the present embodiment, the rotor40 is a magnetic encoder equipped in a hub bearing, and the sensorelement 11 a is a magnetic sensor.

The mount portion 16 in FIG. 7A functions as a stay and is formed tocover a part of the body portion 12 and a part of the signaltransmission component 13. The mount portion 16 includes a mount portionmain body 16 b, which is equipped with a mount bush 16 a and multipleend pieces 16 c, and the like. The mount bush 16 a is, for example, ametallic component having a hole used for affixing the rotationdetection device 10 to a mounted body such as a frame. The multiple endpieces 16 c are for regulating the position of the rotation detectiondevice 10, which is for detecting the rotational state of the rotor 40.Specifically, the end pieces 16 c are for regulating the position of therotation detection device 10 such that the sensor element 11 a of therotation detector component 11 is opposed to the rotor (detected object)40. The end surface 12 a of the body portion 12 is located at a positioncorresponding to the rotation detector component 11 and distant from therotor 40. The sensor elements 11 a are located in the rotation detectorcomponent 11 at a deviated position close to the rotor 40 relative tothe center of the signal transmission component 13.

As described above, the configuration according to the first embodimentproduces the following operation effects. To begin with, as describedabove, the lead frame 11 b of the rotation detector component 11 isjoined with the signal transmission component 13 to form the jointportion 14. Subsequently, the joint portion 14, a part of the signaltransmission component 13, and the rotation detector component 11 areintegrally molded of an epoxy resin (first resin) to form the bodyportion 12 of the rotation detection device 10 (FIG. 1). The rotationdetector component 11 is partially exposed to form the exposed portion11 e. Dissimilarly to a conventional configuration, the presentconfiguration is produced by integrally molding of an epoxy resin,without a holder and a casing. Therefore, the entire size of therotation detection device 10, in particular, the body portion 12, can bereduced. An epoxy resin has an adhesiveness to secure adhesion betweenthe signal transmission component 13 and the rotation detector component11. Thus, the entire size of the rotation detection device 10 can bereduced, while securing its sealing performance (encapsulation).

In the above-described configuration, the exposed portion 11 e is a tipend of the rotation detector component 11 and is distant from the jointportion 14 (FIGS. 1, 5A). With the present configuration, the tip endportion of the rotation detector component 11 can be easily held at thetime of the integral molding. Therefore, the rotation detection device10 can be manufactured without large manufacturing period and burden.

In the above-described configuration, the exposed portion 11 e is aportion at which the rotation detector component 11 is held by theholding member 20 at the time of the integral molding (FIGS. 4, 5A, 5B,5C, and 5D). In the present configuration, the rotation detectorcomponent 11 is held by the holding member 20 during the integralmolding. Therefore, the body portion 12 can be accurately positioned.

In the above-described configuration, the exposed portion 11 e issheathed with an epoxy resin (second resin) partially or entirely (FIGS.6A to 7B). In the present configuration, even though the lead frame 11 b(electric conduction member) is exposed at the exposed portion 11 e, thelead frame 11 b can be sheathed with an epoxy resin. Therefore, electricinsulation of the lead frame 11 b can be secured.

In the above-described configuration, the exposed portion 11 e issheathed with the epoxy resin 15 (FIGS. 6A to 7B). In the presentconfiguration, even though the lead frame 11 b is exposed at the exposedportion 11 e, the sealing property (encapsulation) of the lead frame 11b can be secured.

In the above-described configuration, the exposed portion 11 e partiallyincludes the lead frame 11 b, which is exposed from the surface of therotation detector component 11 (FIG. 6). In the present configuration,the lead frame 11 b, exposed from the surface of the rotation detectorcomponent 11, is sheathed and sealed with the epoxy resin 15. Therefore,insulation and sealing property of the lead frame 11 b can be securable.

In the above-described configuration, both the first resin and thesecond resin are an epoxy resin, which is a thermosetting resin. In thepresent configuration where an epoxy resin is used for both the firstresin and the second resin, the integral molding can be implemented at alow pressure. Therefore, influence exerted on the rotation detectorcomponent 11 can be restrained. It is noted that, a thermoplastics resinmay be employed as both the first resin and the second resin. In thiscase, the melting point of the thermoplastics resin used for the firstresin may be set lower than the melting point of the thermoplasticsresin used for the second resin. In this case, the exposed portions 11 ecan be sheathed (sealed) with the second resin, without melting thefirst resin. Furthermore, combination of other resin materials may beemployable. In any configurations, the rotation detection device 10 canbe manufactured without a large manufacturing period and burden. Thefollowing table 1 shows an example of combinations of resin materialsused for the first resin and the second resin.

TABLE 1 COMBI- NATION FIRST RESIN SECOND RESIN REMARKS 1 THERMO-THERMOSETTING REGARDLESS OF SETTING RESIN MATERIAL RESIN 2 THERMO-THERMOPLASTICS REGARDLESS OF PLASTICS RESIN MATERIAL RESIN (MELTING (M1< M2) (MELTING POINT M2) POINT M1) 3 THERMO- THERMOPLASTICS REGARDLESSOF SETTING RESIN MATERIAL RESIN 4 THERMO- THERMOSETTING REGARDLESS OFPLASTICS RESIN MATERIAL RESIN

In the above-described configuration, the rotation detection deviceincludes the mount portion 16 configured to mount the body portion 12(see FIG. 7). The present configuration facilitates attachment of thebody portion 12 (rotation detection device 10) to an attached object,such as a frame.

In the above-described configuration, the mount portion 16 is integrallymolded of a PBT (third resin) to sheathe one of a part of the bodyportion 12 and a part of the signal transmission component 13 or tosheathe both of a part of the body portion 12 and a part of the signaltransmission component 13 (see FIG. 7A). In the present configuration,integrally molding is implemented with a PBT, and therefore, a desiredshape can be easily achieved.

In the above-described configuration, the body portion 12 has theportion integrally molded with the mount portion 16, and the portion ofthe body portion 12 has the cross section, which is partially orentirely in a circular shape or in an ellipse shape (see FIG. 7B). Inthe configuration where the body portion 12 has a circular cross-sectionpartially or entirely, the body portion 12 can be formed uniformly inall directions. Alternatively, in a configuration where the body portion12 has an elliptical cross-section partially or entirely, rotation ofthe body portion 12 can be restricted.

The manufacturing method for the rotation detection device includes thejoint process joining the lead frame 11 b of the rotation detectorcomponent 11 with the signal transmission component 13; and the bodyportion molding process forming the body portion 12 by integrallymolding of an epoxy resin (first resin) to include the joint portion 14,which is joined in the joint process, a part of the signal transmissioncomponent 13, and the rotation detector component 11, such that a partof the rotation detector component 11 forms the exposed portion 11 eexposed from the body portion 12. Thus, dissimilarly to the conventionalart, a part of the signal transmission component 13 and the rotationdetector component 11 can be integrally molded of an epoxy resin,without a holder and a casing main body, by implementing the jointprocess and the body portion molding process. Thus, the rotationdetection device 10, in particular, the particular body portion 12 canbe downsized. An epoxy resin has an adhesiveness to secure adhesionbetween the signal transmission component 13 and the rotation detectorcomponent 11. Thus, the entire size of the rotation detection device 10can be reduced. In addition, the rotation detection device 10 can bemanufactured without a large manufacturing period and burden.

The above-described method may further include the sheathing process forsheathing the exposed portion 11 e partially or entirely with an epoxyresin (second resin). In the present configuration, the lead frame 11 b(electric conduction member), which is exposed, is sheathed with anepoxy resin in the sheathing process. Therefore, electric insulation issecurable.

In the above-described configuration, the mount portion 16 is integrallymolded of a PBT (third resin) to sheathe one of a part of the bodyportion 12 and a part of the signal transmission component 13 or tosheathe both of a part of the body portion 12 and a part of the signaltransmission component 13 in the mount portion molding process. In thepresent configuration, integrally molding is implemented with a PBT, andtherefore, a desired shape can be easily achieved.

Second Embodiment

The present second embodiment will be described with reference to FIG.8. The configuration of the rotation detection device 10 according tothe second embodiment is substantially equivalent to that of the firstembodiment. Therefore, difference from the configuration of the firstembodiment will be mainly described as follows.

The second embodiment differs from the above-described first embodimentin the configuration of the mount portion 16. FIG. 8 is a front viewshowing the rotation detector component 11 according to the secondembodiment. In FIG. 8, the mount portion 16 includes the mount portionmain body 16 b equipped with the mount bush 16 a, a recessed portion 16e, and the like. The configuration of the second embodiment is equippedwith the recessed portion 16 e in place of the multiple end pieces 16 c.The recessed portion 16 e is formed in the outermost periphery of acircular portion of the mount portion main body 16 b to receive anO-ring 16 d. In the example of FIG. 8, the mount portion main body 16 bis formed such that the position of the mount bush 16 a is shifted(rotated) by 90 degrees, compared with the configuration of FIG. 7A. Inthe second embodiment, the mount portion 16 has a differentconfiguration from that of the first embodiment. Therefore, the secondembodiment is configured to produce an operation effect equivalent tothat of the first embodiment.

Other Embodiment

The present disclosure is not limited to the above-described first andsecond embodiments. For example, following embodiments may beincorporated in the present disclosure.

In the above-described first embodiment with reference to FIG. 7A, themount portion 16 includes the mount portion main body 16 b extended inthe direction perpendicular to the main surface of the rotor 40.Alternatively, as shown in FIG. 9, the mount portion main body 16 b maybe extended in parallel with the main surface of the rotor 40. It isnoted that, the mount portion main body 16 b may be extended in anotherdirection such that the mount portion main body 16 b does not interferewith the rotor 40. That is, the mount portion 16 of the first embodimentmay be extended similarly to the mount portion 16 described in thesecond embodiment with reference to FIG. 8. In consideration of therelative position of the object, to which the rotation detection device10 is attached, the mount portion 16 may be extended at an angle θrelative to the main surface of the rotor 40. In this case, the angle θmay be in the following range: 0 degree<θ<180 degrees. In theseconfigurations, the mount portion 16 has a different configuration fromthose of the first and second embodiments and produces an operationeffect equivalent to those of the first and second embodiments.

In the first and second embodiments described with reference to FIGS. 1,5A, 5B, 5C, and 5D, the body portion 12 is formed by integrally moldingof an epoxy resin the tip end surface of the rotation detector component11, which is held by the holding member 20. In place of theconfiguration or in addition to the configuration, the body portion 12may be formed by integrally molding of an epoxy resin, while a portionof the rotation detector component 11, which is other than the tip endsurface, is held by the holding member 20. FIGS. 10A and 10B showexamples of the body portion 12 formed in this way. These examples showthe recessed portions 20 a of the holding members 20, which havedifferent shapes, and the exposed portions 11 e, which have differentconfigurations, respectively. Therefore, these examples produceoperation effects equivalent to those of the first and secondembodiments. It is noted that, in the examples of FIGS. 10A and 10B, theelectric conduction member (lead frame 11 b) may be sheathed with aresin when exposed, as described above with reference to FIGS. 6A, 6B,6C, and 6D.

In the example of FIG. 10A, the body portion 12 is formed by integrallymolding of an epoxy resin to include one lateral side of the rotationdetector component 11, which is held by the holding member 20. In thisexample, the lead frame 11 b is not exposed from or projected from theone lateral side of the rotation detector component 11. In the exampleof FIG. 10A, the one lateral side of the rotation detector component 11has the exposed portion 11 e. Alternatively, the body portion 12 may beintegrally molded such that each of the lateral sides of the rotationdetector component 11 has the exposed portion 11 e. In this case, theend surface 12 a may be formed in the longitudinal direction of the bodyportion 12.

FIG. 10E shows an example of the body portion 12 integrally molded of anepoxy resin while corners of the rotation detector component 11 are heldby the holding member 20. In the example of FIG. 10B, the tip endportion of the rotation detector component 11 has two corners formingthe exposed portions 11 e, respectively. The body portion 12 may beintegrally molded such that one of the two corners of the rotationdetector component 11 forms the exposed portion 11 e. Alternatively, thebody portion 12 may be integrally molded such that three corners of therotation detector component 11 form the exposed portions 11 e.Alternatively, the body portion 12 may be integrally molded such thatall the four corners of the rotation detector component 11 form theexposed portions 11 e.

In the above-described first and second embodiments described withreference to FIGS. 2A and 2B, the sensor element 11 a is embedded in therotation detector component 11. Alternatively, the sensor element 11 amay be a separate component from the rotation detector component 11. Inthe present configuration, the processing circuit 11 c of the rotationdetector component 11 needs a signal line and a lead frame for receivinga signal from the sensor element 11 a. In addition, in the body portionmolding process to form the body portion 12, the sensor element 11 a maybe integrally molded of the first resin together with the rotationdetector component 11, the joint portion 14, and the signal transmissioncomponent 13. The present configuration is different from theabove-described configurations in separate provision of the sensorelement 11 a from the rotation detector component 11. Therefore, thepresent configuration produces an effect equivalent to configurations ofthe first and second embodiments.

In the above-described first and second embodiments with reference toFIGS. 2A and 2B, the processing circuit 11 c is configured with thesemiconductor chip equipped with the circuit, which is configured toprocess the detection signal from the sensor element 11 a.Alternatively, the processing circuit 11 c may be configured with asemiconductor device, such as an IC and/or an LSI, or may be configuredwith a circuit board equipped with a circuit component, such as asemiconductor device, a circuit element, and/or a connection component.The present configuration merely differs from the above-describedconfigurations in the structure of the processing circuit 11 c and hasthe function to process the detection signal from the sensor element 11a. The present configuration also produces an operation effectequivalent to those of the first and second embodiments.

In the above-described first and second embodiments with reference toFIGS. 5A, 5B, 5C, 5D, 7A, 7B, and 8, an epoxy resin (EP), which is oneof a thermosetting resin, is employed as the first resin, and the secondresin, and a poly butylene terephthalate (PBT), which is one of athermoplastics resin, is employed as the third resin. In addition to thecombinations shown in the table 1, another combination of resinmaterials may be employed. For example, a phenol resin (PF), a melamineresin (MF), an urea resin (urea resin, UF), an unsaturated polyesterresin (UP), an alkyd resin, an polyurethane (PUR), a thermosettingpolyimide (PI), and/or the like may be employed as the thermosettingresin. For example, a polyethylene (PE), a high-density polyethylene(HDPE), a medium-density polyethylene (MDPE), a low-density polyethylene(LDPE), a polypropylene (PP), a polyvinyl chloride (PVC), apolyvinylidene chloride, a polystyrene (PS), a polyvinyl acetate (PVAc),a polytetrafluoroethylene (PTFE), an acrylonitrile butadiene styrene(ABS), an acrylonitrile styrene (AS), a polymethylmethacrylate (acrylicresin, PMMA), a polyamide (PA), a nylon, a polyacetal (POM), apolycarbonate (PC), a denatured polyphenylene ether (m-PPE, denaturedPPE, PPO), a polyethylene terephthalate (PET), a glass-fiber reinforcedpolyethylene terephthalate (GF-PET), a cyclic polyolefin (COP), apolyphenylene sulfide (PPS), a polysulfone (PSF), a polyether sulfone(PES), an amorphous polyarylate (PAR), a liquid crystal polymer (LCP), apolyether ether ketone (PEEK), a thermoplastic polyimide (PI), apolyamide imide (PAI), and/or the like may be employed as thethermoplastics resin. In place of or in addition to the thermoplasticsresin or the thermosetting resin, a fiber-reinforced plastic, such as aglass-fiber reinforced plastic (GFRP), a carbon-fiber reinforced plastic(CFRP), and/or the like, may be employed. With any of theabove-described resin materials, an operation effect equivalent to thoseof the first and second embodiments can be produced.

The above-described rotation detection device may include: the rotationdetector component configured to detect the rotational state of therotor and to send the rotational detection signal; the signaltransmission component electrically connected with the rotation detectorcomponent and configured to transmit the rotational detection signal toan external device; and the body portion holding a part of the signaltransmission component and the rotation detector component. The bodyportion may be integrally molded of the first resin, after joining thelead frame of the rotation detector component with the signaltransmission component, to cover the joint portion, a part of the signaltransmission component, and the rotation detector component. Inaddition, a part of the rotation detector component may form the exposedportion exposed from the body portion.

The present configuration is produced by integrally molding the firstresin to include a part of the signal transmission component, and therotation detector component, without a holder and a casing, dissimilarlyto a conventional configuration. Therefore, the entire size of therotation detection device, in particular, the body portion, can bereduced. In a case where an adhesive resin material is employed as thefirst resin, the signal transmission component and the rotationdetector, which includes the lead frame and the like, can be securelyadhered with the first resin, and sealing (encapsulation) can be alsosecurely implemented. In addition, the entire size of the rotationdetection device can be reduced, compared with a conventionalconfiguration.

The rotor may be in various shapes. Generally, the rotor may be in adisc shape or may be in an annular shape (doughnut shape) or the like.The rotational state may be a condition, which relates to rotation, suchas a rotational speed, a rotational angle, and/or the like, and mayinclude a stopping state (motionless state). The rotation detectorcomponent may include the sensor element and the signal processing unit.The sensor element and the signal processing unit may be configured totransmit a signal. The sensor element and the signal processing unit maybe integrated with each other or may be separately provided from eachother. The sensor element may arbitrarily employ various elements, whichare configured to detect rotation of the rotor. Generally, the sensormay be a magnetic sensor, a sound wave sensor, and/or the like. Thesignal processing unit may be configured to implement a processing tosend the rotational detection signal according to the detection signalfrom the sensor element in a predetermined signal format, such as apulse signal, a digital data signal, an analog signal, and/or the like.The signal transmission component may arbitrarily employ variouscomponents configured to transmit or conduct the rotational detectionsignal. The signal transmission component may be, for example, a cable,a wire, an electric line, such as a shielded line, and/or an opticalcable. The lead frame is equipped to the rotation detector component tofunction as an electric conduction member to connect the componentselectrically therebetween. The lead frame may be in various shapes, maybe configured with one or more elements, and may be formed of variousmaterials. The lead frame may be projected from the rotation detectorcomponent or may be exposed from the surface of the rotation detectorcomponent. In place of the lead frame or in addition to the lead frame,various conduction members, such as a lead wire, a connection pin, aterminal, and/or the like may be employable.

The first resin may be arbitrarily selected from various resinmaterials, which can be integrally molded with the sensor element, thesignal transmission component, and the like. For example, the firstresin may be arbitrarily selected from various resin materials, such asa thermosetting resin, a thermoplastics resin, and another resinmaterial. The thermosetting resin may be a resin material, which causesnoninvertible polymerization to form a hardened mesh configuration whenbeing heated. The thermoplastics resin may be a resin material, which issoftened when being heated beyond its glass transition temperature orits melting point and which is formed in a target shape when beingcooled thereafter. The first resin may be a resin material formed byarbitrarily mixing or blending various resin materials, such as athermosetting resin, a thermoplastics resin, and another resin material.For example, an epoxy resin (EP), a phenol resin (PF), a melamine resin(MF), an urea resin (UF), an unsaturated polyester resin (UP), an alkydresin, an polyurethane (PUR), a thermosetting polyimide (PI), and/or thelike may be employed as the thermosetting resin.

For example, a commodity resin material, an engineering plasticmaterial, a super engineering plastic material, and/or the like may beemployed as the thermoplastics resin. For example, a polyethylene (PE),a high-density polyethylene (HDPE), a medium-density polyethylene(MDPE), a low-density polyethylene (LDPE), a polypropylene (PP), apolyvinyl chloride (PVC), a polyvinylidene chloride, a polystyrene (PS),a polyvinyl acetate (PVAc), a polytetrafluoroethylene (PTFE), anacrylonitrile butadiene styrene (ABS), an acrylonitrile styrene (AS), apolymethylmethacrylate (acrylic resin, PMMA), and/or the like may beemployed as the commodity resin material. For example, a polyethyleneterephthalate (PET), a polyamide (PA), a nylon, a polyacetal (POM), apolycarbonate (PC), a denatured polyphenylene ether (m-PPE, denaturedPPE, PPO), a polyethylene terephthalate (PET), a glass-fiber reinforcedpolyethylene terephthalate (GF-PET), a cyclic polyolefin (COP), and/orthe like, may be employed as the engineering plastic resin. For example,a polyphenylene sulfide (PPS), a polysulfone (PSF), a polyether sulfone(PES), an amorphous polyarylate (PAR), a liquid crystal polymer (LCP), apolyether ether ketone (PEEK), a thermoplastic polyimide (PI), apolyamide-imide (PAI), and/or the like may be employed as the superengineering plastic resin. A fiber-reinforced plastic may be employed asthe first resin, in place of one of the thermosetting resin and thethermoplastics resin or in place of both the thermosetting resin and thethermoplastics resin. A fiber-reinforced plastic may be employed as thefirst resin, in addition to one of the thermosetting resin and thethermoplastics resin or in addition to both the thermosetting resin andthe thermoplastics resin. For example, a glass-fiber reinforced plastic(GFRP), a carbon-fiber reinforced plastic (CFRP), and/or the like may beemployed as the fiber-reinforced plastic.

The exposed portion may be a tip end portion of the rotation detectorcomponent, distant from the joint portion. With the presentconfiguration, the tip end portion of the rotation detector can beeasily held at the time of the integral molding. Therefore, the rotationdetection device can be manufactured without large manufacturing periodand burden.

The exposed portion may be a portion of the rotation detector componentheld by the holding member when the body portion is integrally molded.The exposed portion is a trace of the holding member, which holds therotation detector component during the integral molding of the firstresin. In the present configuration, the rotation detector is held bythe holding member during the integral molding. Therefore, the bodyportion can be accurately positioned.

The exposed portion may be sheathed with the second resin partially orentirely.

It is noted that, an electric conduction member may be exposed in theexposed portion of the rotation detector component, regardless of beingprojected or not. In the present configuration, in which the exposedportion is sheathed with the second resin partially or entirely, theelectric conduction member, which is exposed, is sheathed with thesecond resin. Therefore, electric insulation is securable.

The second resin may be arbitrarily selected from various electricallyinsulative resin materials. For example, the second resin may bearbitrarily selected from the above-described resin materials such asthe thermosetting resin, the thermoplastics resin, or another resin. Thesecond resin may be equivalent to the first resin or may be differentfrom the first resin. The second resin may include multiple kinds ofresin materials, which are different from each other in property. Afiber-reinforced plastic may be employed as the second resin, in placeof one of the thermosetting resin and the thermoplastics resin or inplace of both the thermosetting resin and the thermoplastics resin. Afiber-reinforced plastic may be employed as the second resin, inaddition to one of the thermosetting resin and the thermoplastics resinor in addition to both the thermosetting resin and the thermoplasticsresin.

The exposed portion may be sealed with the second resin. In the presentconfiguration, even though the electric conduction member is exposed atthe exposed portion, the sealing property (encapsulation) of theelectric conduction member can be secured.

A part of the exposed portion may include an electric conduction memberexposed from the surface of the rotation detector component. In thepresent configuration, the electric conduction member, which is exposedfrom the surface of the rotation detector, is sheathed and sealed withthe second resin. Therefore, insulation and sealing property of theelectric conduction member can be securable.

Each of the first resin and the second resin may be a thermosettingresin. Alternatively, a melting point of a thermoplastics resin employedas the first resin may be lower than a melting point of a thermoplasticsresin employed as the second resin. In the present configuration where athermosetting resin is used for both the first resin and the secondresin, the integral molding can be implemented at a low pressure.Therefore, influence exerted on the rotation detector component can berestrained. Alternatively, in a configuration in which the melting pointof the thermoplastics resin employed as the first resin is lower thanthe melting point of the thermoplastics resin employed as the secondresin, the exposed portion can be sheathed and sealed with the secondresin, without melting the first resin. In any configurations, therotation detection device can be manufactured without a largemanufacturing period and burden.

The rotation detection device may further include the mount portionconfigured to mount the body portion. The present configurationfacilitates attachment of the body portion (rotation detection device)to an attached object, such as a frame. The mount portion may functionas a stay and may be formed of various materials in various shapes,arbitrarily.

The mount portion may be integrally molded of the third resin to cover:one of a part of the body portion and a part of the signal transmissioncomponent; or both of a part of the body portion and a part of thesignal transmission component. In the present configuration, integrallymolding is implemented with the third resin, and therefore, a desiredshape can be easily achieved. The third resin may be arbitrarilyselected from various resin materials, which can be integrally moldedwith the body portion and the signal transmission component. Forexample, the third resin may be arbitrarily selected from theabove-described resin materials such as the thermosetting resin, thethermoplastics resin, or another resin. The third resin may beequivalent to the first resin and/or the second resin. Alternatively,the third resin may be different from the first resin and the secondresin. The third resin may include multiple kinds of resin materials,which are different from each other in property. A fiber-reinforcedplastic may be employed as the third resin, in place of one of thethermosetting resin and the thermoplastics resin or in place of both thethermosetting resin and the thermoplastics resin. A fiber-reinforcedplastic may be employed as the third resin, in addition to one of thethermosetting resin and the thermoplastics resin or in addition to boththe thermosetting resin and the thermoplastics resin. Another materialsuch as a metallic material and/or a carbon-fiber material may beemployed.

The body portion may have a portion (integrally-molded portion), whichis integrally molded with the mount portion, and the portion of the bodyportion may have the cross section, which is partially or entirely in acircular shape or in an ellipse shape.

The cross section may represent the cross sectional shape of the outerperiphery of the body portion. In the present configuration, the bodycan be uniformly formed in all directions, in a case where the crosssection of the body is partially or entirely in a circular shape. Thecross section of the body may not be limited to an exactly circularshape and may have unevenness in an allowable range. Alternatively, in acase where the cross section of the body is partially or entirely in anellipse shape, rotation of the body can be restricted. In this case, thecross section of the body may have unevenness in an allowable range.

The above-described rotation detection device may include: the rotationdetector component configured to detect the rotational state of therotor and to send the rotational detection signal; the signaltransmission component electrically connected with the rotation detectorcomponent and configured to transmit the rotational detection signal toan external device; the body portion holding a part of the signaltransmission component and the rotation detector component; and themount portion configured to mount the body portion. The manufacturingmethod for the rotation detection device may include: the joint processjoining the lead frame of the rotation detector component with thesignal transmission component; and the body portion molding processforming the body portion of the first resin by integrally molding thejoint portion joined in the joint process, a part of the signaltransmission component, and the rotation detector component, such that apart of the rotation detector component has an exposed portion, which isexposed from the body portion.

Thus, a part of the signal transmission component and the rotationdetector component can be integrally molded of the first resin byimplementing the joint process and the body portion molding process,without a holder and a casing main body, dissimilarly to theconventional art. Thus, the rotation detection device, in particular,the particular body portion can be downsized. In a configuration wherethe first resin has adhesiveness, the signal transmission component andthe rotation detector component can be secured with each other via thefirst resin. Thus, the entire size of the rotation detection device canbe reduced. In addition, the rotation detection device can bemanufactured without a large manufacturing period and burden.

The manufacturing method may further include the sheathing processpartially or entirely sheathing the exposed portion with the secondresin. In the present configuration, the electric conduction member,which is exposed in the exposed portion, is sheathed with the secondresin in the sheathing process. Therefore, electric insulation issecurable.

The manufacturing method may further include the mount portion moldingprocess integrally molding the mount portion of the third resin tocover: one of a part of the body portion and a part the signaltransmission component; or both of a part of the body portion and a partthe signal transmission component. In the present configuration,integrally molding is implemented with the third resin, and therefore, adesired shape can be easily achieved.

The above structures of the embodiments can be combined as appropriate.It should be appreciated that while the processes of the embodiments ofthe present disclosure have been described herein as including aspecific sequence of steps, further alternative embodiments includingvarious other sequences of these steps and/or additional steps notdisclosed herein are intended to be within the steps of the presentdisclosure.

While the present disclosure has been described with reference topreferred embodiments thereof, it is to be understood that thedisclosure is not limited to the preferred embodiments andconstructions. The present disclosure is intended to cover variousmodification and equivalent arrangements. In addition, while the variouscombinations and configurations, which are preferred, other combinationsand configurations, including more, less or only a single element, arealso within the spirit and scope of the present disclosure.

What is claimed is:
 1. A rotation detection device comprising: arotation detector component configured to detect a rotational state of arotor and to send a rotational detection signal; a signal transmissioncomponent electrically connected with a lead frame of the rotationdetector component and configured to transmit the rotational detectionsignal to an external device; and a body portion holding the rotationdetector component and a part of the signal transmission component,wherein the body portion is integrally molded of a first resin, afterjoining the lead frame of the rotation detector component with thesignal transmission component to form a joint portion between the leadframe and the signal transmission component, to cover the joint portion,the rotation detector component, and the part of the signal transmissioncomponent, a part of the rotation detector component forms an exposedportion exposed from the body portion, the exposed portion is a tip endportion of the rotation detector component and distant from the jointportion, only the exposed portion is held by a holding member when thebody portion is integrally molded, and the exposed portion has a tip endsurface, which is distant from the joint portion and exposed.
 2. Therotation detection device according to claim 1, wherein the exposedportion is partially or entirely sheathed with a second resin.
 3. Therotation detection device according to claim 2, wherein the exposedportion is sealed with the second resin.
 4. The rotation detectiondevice according to claim 2, wherein a part of the exposed portionincludes an electric conduction member exposed from a surface of therotation detector component.
 5. The rotation detection device accordingto claim 2, wherein each of the first resin and the second resin is athermosetting resin, or a melting point of a thermoplastics resinemployed as the first resin is lower than a melting point of athermoplastics resin employed as the second resin.
 6. The rotationdetection device according to claim 1, further comprising: a mountportion configured to mount the body portion.
 7. The rotation detectiondevice according to claim 6, wherein the mount portion is integrallymolded of a third resin to cover: one of a part of the body portion andthe part of the signal transmission component; or both of the part ofthe body portion and the part of the signal transmission component. 8.The rotation detection device according to claim 6, wherein the bodyportion has an integrally-molded portion, which is integrally moldedwith the mount portion, and the integrally-molded portion has a crosssection, which is partially or entirely in a circular shape or in anellipse shape.
 9. The rotation detection device according to claim 1,wherein the tip end surface is on an opposite side of the tip endportion from the body portion, and the tip end surface is exposed fromthe body portion.
 10. The rotation detection device according to claim9, wherein the tip end portion is extended from the body portion in anextended direction, and tip end surface is directed in the extendeddirection.
 11. A manufacturing method for a rotation detection device,the rotation detection device comprising: a rotation detector componentconfigured to detect a rotational state of a rotor and to send arotational detection signal; a signal transmission componentelectrically connected with a lead frame of the rotation detectorcomponent and configured to transmit the rotational detection signal toan external device; a body portion holding the rotation detectorcomponent and a part of the signal transmission component; and a mountportion configured to mount the body portion, the manufacturing methodcomprising: joining the lead frame of the rotation detector componentwith the signal transmission component to form a joint portion betweenthe lead frame and the signal transmission component; and forming thebody portion of the first resin by integrally molding the joint portion,the rotation detector component, and the part of the signal transmissioncomponent, such that a part of the rotation detector component has anexposed portion, which is exposed from the body portion, wherein theexposed portion is a tip end portion of the rotation detector componentand distant from the joint portion, only the exposed portion is held bya holding member in the forming, and the exposed portion has a tip endsurface, which is distant from the joint portion and exposed.
 12. Themanufacturing method for the rotation detection device, according toclaim 11, further comprising: sheathing partially or entirely theexposed portion with a second resin.
 13. The manufacturing method forthe rotation detection device, according to claim 11, furthercomprising: integrally molding the mount portion of a third resin tocover: one of a part of the body portion and the part of the signaltransmission component; or both of the part of the body portion and thepart of the signal transmission component.
 14. The manufacturing methodaccording to claim 11, wherein the tip end surface is on an oppositeside of the tip end portion from the body portion, and the tip endsurface is exposed from the body portion.
 15. The manufacturing methodaccording to claim 14, wherein the tip end portion is extended from thebody portion in an extended direction, and tip end surface is directedin the extended direction.